diff --git a/ChangeLog b/ChangeLog
index a44fd778b..cf3df3231 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2010-12-30  Wolfgang Lux  <wolfgang.lux@gmail.com>
+
+	* Source/NSMenuView.m (-trackWithEvent:):
+	Make pop up menus in Macintosh menu style behave more similar to
+	OS X. In particular, when the user clicks the button, the menu
+	stays open until the next click.
+
 2010-12-30  Wolfgang Lux  <wolfgang.lux@gmail.com>
 
 	* Source/NSMenuView.m (-update):
diff --git a/Source/NSMenuView.m b/Source/NSMenuView.m
index 39e891178..fcd926075 100644
--- a/Source/NSMenuView.m
+++ b/Source/NSMenuView.m
@@ -1465,7 +1465,15 @@ static NSMapTable *viewInfo = 0;
       eventMask |= NSLeftMouseDownMask;
     }
 
-  if ([self isHorizontal] == YES)
+  /* We attempt to mimic Mac OS X behavior for pop up menus. If the user
+     presses the mouse button over a pop up button and then drags the mouse
+     over the menu, the is closed when the user releases the mouse. On the
+     other hand, when the user clicks on the button and then moves the mouse
+     the menu is closed upon the next mouse click. */
+  if ([self isHorizontal] == YES ||
+      ([[self menu] _ownedByPopUp] == YES &&
+       NSInterfaceStyleForKey(@"NSMenuInterfaceStyle", self)
+       == NSMacintoshInterfaceStyle))
     {
       /*
        * Ignore the first mouse up if nothing interesting has happened.